Method of separating butterfat from globules thereof



Patented Nov. 11, 1952 srArEs PATENT OFFICE- can of Pennsylvania Bic Drawin Application A prn Is, 1951, Serial No. 221323 8 Claims.

the globule contains the constituents of butterfat andis surroundedby other materials, an outer layer oi which is of phospholipids and proteins which forms a proteinaceous membrane that is the principal barrier to coalescence or merging ofthebutterfat; globules.-

Butterfat; or butter on which is melted unetu: ous buteerfat, is the principal 'constituent of 7 commercial butter made by churning, the chief difiierence between the two beingthat butter produced by churning includes some of. the pro teinaceous material of; butterfat globules andsm ll quantities of serum.- This is due to theme that in making butter by churning whole I miIkQbf cream separated. from it the butterfat globules coalsceto form bodies that may vary mead roughly corn-parable to; that of grains; of; wheat to that of peas, and which. occlude other constituents These coalesced bodies are suitably sepaiatedirom. the-churned serum, washedaiid worked into a homogeneous mass? with or without the addition of salt to form eomm'icial butter which contains some; at the; protemadebus mste'fiai of the butterfat globules, I as well as some of the or dream serum. Th's" latter materials are susceptible to micro-g biolo cal attack, which is a princii ai. reason for the: 'e'fidficy' or butter to spoil aiid become rancid; e5

TI l object semis iniihtio'n is to provide a pr tical and eiiicieiit, low-cost method of sep' gbuttrfat from globu es thereof, and m- V mdvlilg thesesa rafie butteiiat f om these m thati cohtaiiied the biitterfat globules, wherebyiw relatively large percentages of the svanabie but-- terfat in substantially pure form are removed.

In the practice of this invention in its ap-V plicability to recovering butterfat fromv normal, milli serum, although it may be removed from}; other Serums containing it, the major portion of 7 its butterfat content is separated from the milk by passing it through a conventional. cream. sep- V arator to remove cream containing; preferabl'yi more percent of butterfat, which in the l globular form explained is in'the dispersed phase of. a; miikl or cream emulsion. Proteinaceous membranes of butterfat of the cream are removed or dispersed from the globules to permit th butterfat constituents thereof to coalesce 2i thoroughly mixing with the cream one or more of anorganic compound or compounds of the group having chemical;- and physical or functional, characteristics presently to be explained. The organic compounds o mixed with the cream are, in efiect, de-emulsifying agents which dis-a perse in various ways proteinaceous membranes of the butterfat globules that are the principal barrier to coalescence or merging of the butterfat content of the many dispersed globules.

This invention is predicated; in part, upon our discovery that the efiective agents for this pur pose are organic compounds of the group in' whichmolecules thereof contain carbon atoms: from 3' through about 10 in number and also, contain hydrogen, and. which materially lower the interfacial tension between the continuous, phase material of the liquid medium or cream emulsion arid the butterfat within the globules that are suspended in the dispersed phase of the emulsion; Examples of such compounds will presently be explained. 1

To permit coalescence of the butterfat constituents of the globules which have their mteinaceous membranes dispersed by the organic compound or compounds added to the mixture, the mixture is heated to a temperature of not less than about. F. and below its boiling point." This heating. of the mixture melts the butterf at 1 constituentsor the globules thereof so that such. consituents merge with each other to form but ter oil; which is thereafter suitably separated from the remainder of the mixture. While in some cases the mixture maybe heated to a temperaturc as low as 1-20 F. it is preferably heated,- toa. temperature of not less than about F; This elevated temperature is maintained until the released butter oil is separated from the re mainder of the mixture. Thereafter the butter oil is preferably washed with hot water, which may be at a temperature of about F., and centrifuged through. a cream separator to remove any impurities that may be present, ineluding such small portion of the de-emulsiiying organic compound as may not remain in. the

acid (cu-non, n-capmic acid (censor; mtutyi V V diethyleneglyc'ol' mohobutyl emer- (Gel-11303), propionic acid (CsHsOL), n-butyrieamine (C4H11N), isoamyl amine (C5H13N) methyl ethyl ketone (C4H1O) and Tergitol-7, which is a. trade name for a de-emulsifying mixture havingas its active agents for the purpose of this invention diethylene glycol monobutyl ether (C8H1803) and sodium 3, 9 diethyl tridecyl-6- sulphate (C1'1H35SO4Na) All of these compounds contain polar groupings, and we now believe that the action of all organic compounds operable in the practice of this invention is dependent on the presence of groupings that are polar or at least exert some polar action.

The following procedures for the practice of the invention are given by way of example, and not of limitation.

Example 1.-To 17 pounds of raw cream containing 46.5% butterfat there were added 9 fluid ounces of Tergitol-7, described above, and the mixture was stirred while its container was in awater bath heated to atemperature of about 180 F. for about fifteen minutes. After removing the container and permitting it'to stand for about 10 minutes, the butter oil released by the procedure separated from and floated on top of the remaining aqueous material of the cream. Theaqueous lower layer was removed by'siphoning, but the floating butter oil may readilyfbe removed by decanting orlby passing the entire mixture through a cream separator. The crude butter oil was then passed through a conventional cream separator which had previously been heated to the usual temperature for, and so adjusted as would normally be done, to recover plastic cream from milk. Clear butter oil having'a high degree of purity was collected at r the cream outlet of the separator," while a very" small amount'of milk-colored liquid drained from the skim milk outlet of the separator. The butter oil was washed with hot water at a temperature of about 180", F. and again passed through the cream separator which had pr'e' viously been cleaned. The yield, excluding fat that remained in the separator and was not reclaimed, was 7 pounds, 3 ounces, or in excess of 90% based on the butterfat content of the cream. g

Example 2. -To 16 pounds of raw cream containing 40.0% butterfat were added fluid ounces of n-butyl alcohol. This mixture after being'processed in the same manner as described in "Example 1, yielded 6 pounds, O'ounces of butter oil, or in excess of 90% based on the butterfat content of the cream.

Example 3. To 16.5 pounds of raw cream containing 42.0% butterfat were added 25 fluid ounces of diethyleneglycol monobutyl ether.

This mixture, after being'processed in the same manner as described in example 1 yielded 6' pounds, '7 ounces of butter oil, or in excess oi 90%-based on the butterfat content of the cream.

Example 4.To 16 pounds of raw cream containing' 40.5% butterfat were .added' 25 fluid ounces of n-butyric acid.' This'mixture, after being processed in the same manner as described in example 1, yielded 6 pounds, 2 ounces of butter oil which yield is also in excess of practice of our invention, We have found, for

example, that sodium hydroxide (NaOH) when used in sufiicient concentration to de-emulsify,

substantially completely saponifies the butterfat which fact renders this agent useless. Sodium chloride, (NaCl) was found to have no de-emulsi- 1' fying power up to 10% of the weight of the cream. We also found that concentrated hydrochloric acid (HCl) when added at not less than 30% by weight of the cream, de-emulsified the cream by substantially digesting the proteins of the cream, rendering the serum phase essentially useless.

The butter oil recovered in the practice of this invention is substantially pure, free from the deleterious effect of milk serum materials present in commercial churned butter, and may be stored at room temperatures for long periods of time Without becoming rancid or otherwise spoiled or impaired as a result of microbiological action. It may be used to make butter, the same as commercial butter produced by churning, by adding milk serum constituents and salt to it, or by merely adding milk serum constituents if sweet butter is desired. Butter oil recovered in the practice of this invention is also entirely suitable as a source of butterfat in the formulation of ice cream mixes, and in the reconstitution of non-fat dry milk to whole milk.

.According to the provisions of the patent statutes, we have explained the-principle of our invention and its mode of operation, "and have given specific examples, of howit maybe practiced. However, We desire to have it understood that, within the scope of the appended claims, the invention may be practiced otherwise than the specific examples we have described.

We claim as our invention:

l, The method of separating butterfat from globules thereof that are suspended in a liquid medium, comprising dispersing proteinaceous membranes of such globules to permit butterfat constituents thereof to coalesce by mixing with said globule-containing medium at least one organic compound containing from 3 to 10 carbon atoms, inclusive, together with hydrogen and an element from the group consisting of oxygen and nitrogen, said compound being soluble in said medium and materially lowering interfacial tension between said medium and butterfat within said globules, heating the mixture to atemperature of not less than about F. and below the boiling point thereof whereby butterfat constituents of said globules are melted and merged with each other to form butter oil, and thereafterseparating such oilfrom the remainder of the mixture.

2. The method of separating butterfat from globules thereof that are suspended in cream, comprising dispersing proteinaceous membranes of such globules to permit butterfat constituents thereof to coalesce by mixing with said cream at least one organic compound containing from 3 to 10 carbon atoms, inclusive, together with hydrogen and anelement from the group consisting of oxygen and'nitrogen, said compound being soluble in said medium and materially lowering interfacial'tension between the cream and butterfat within said globules, heating the mixture to a temperature of not less than about F.. and. below the boiling point thereof whereby butterfat constituents of said globules are melted and merged with each other to form butter oil, and v thereafter separating such oil mainder of the mixture. 3. The method of separating butterfat from globules thereofthat are suspended in cream,

comprising dispersing proteinaceous membranes of such globules to permit butterfat constituents thereof to coalesce by mixing with said cream at leasttone organic compound containing from from the re- 3 to 10 carbon atoms, inclusive, together with hydrogen and an element from the group consisting of oxygen and nitrogen, said compound being soluble in said medium and materially lowering interfacial tension between the cream and butterfat within said globules, heating the mixture to a temperature of not less than about 135 F. and below the boiling point thereof whereby butterfat constituents of said globules are melted and merged with each other to form butter oil, separating such oil from the remainder of the so-heated mixture, washing the butter oil with water at a temperature of not less than about 135 F. and below the boiling point thereof, and separating the washed butter oil from such water and its content of impurities washed from the butter oil.

4. A method accordin to claim 1, said organic compound being n-butyl alcohol.

5. A method according to claim 1, said organic compound being diethyleneglycol monobutyl ether.

STUART PAT'I'ON. CHARLES M. STINE.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,404,034 Buxton July 16, 1946 2,461,117 Lindgren Feb. 8, 1949 2,547,281 Petty Apr. 3, 1951 

1. THE METHOD OF SEPARATING BUTTERFAT FROM GLOBULES THEREOF THAT ARE SUSPENDED IN A LIQUID MEDIUM, COMPRISING DISPERSING PROTEINACEOUS MEMBRANES OF SUCH GLOBULES TO PERMIT BUTTERFAT CONSTITUENTS THEREOF TO COALESCE BY MIXING WITH SAID GLOBULE-CONTAINING MEDIUM AT LEAST ONE ORGANIC COMPOUND CONTAINING FROM 3 TO 10 CARBON ATOMS, INCLUSIVE, TOGETHER WITH HYDROGEN AND AN ELEMENT FROM THE GROUP CONSISTING OF OXYGEN AND NITROGEN SAID COMPOUND BEING SOLUBLE IN SAID MEDIUM AND MATERIALLY LOWERING INTERFACIAL TENSION BETWEEN SAID MEDIUM AND BUTTERFAT WITHIN SAID GLOBULES, HEATING THE MIXTURE TO A TEMPERATURE OF NOT LESS THAN ABOUT 120* F. AND BELOW THE BOILING POINT THEREOF WHEREBY BUTTERFAT CONSTITUENTS OF SAID GLOBULES ARE MELTED AND MERGED WITH EACH OTHER TO FORM BUTTER OIL, AND THEREAFTER SEPARATING SUCH OIL FROM THE REMAINDER OF THE MIXTURE. 